I've bought some refurbished 1l PCs in places where others might have bought RPi. Drawbacks are more energy consumption and, generally, no GPIO (at least built-in). Also bigger in size. I have one Lenovo M600 which has four serial ports (DB9) and one parallel port (DB25) on some kind of extension module. Because of the module it also has more space for cooler, thus making it passively cooled.
OS: Gentoo Linux x86_64
Host: 10GJS01G00 (ThinkCentre M600)
Kernel: Linux 6.6.101-M600-minimal-0.1
Uptime: 1 day, 23 hours, 59 mins
Packages: 567 (emerge)
Shell: bash 5.2.37
Display (ACER H235HL): 1920x1080 @ 60 Hz in 23" [External]
Terminal: tmux 3.5a
CPU: Intel(R) Celeron(R) N3010 (2) @ 2.24 GHz
GPU: Intel Atom/Celeron/Pentium Processor x5-E8000/J3xxx/N3xxx Integrated Graphics Controller @ 0.60 GHz [Integrated]
Memory: 312.46 MiB / 7.37 GiB (4%)
Swap: 0 B / 32.00 GiB (0%)
Disk (/): 8.90 GiB / 19.94 GiB (45%) - xfs
Disk (/var/cache/pkg): 4.41 GiB / 4.84 GiB (91%) - ext4
Fast it ain't, but does fit the bill.
I think I had my last windows install (Win98) on bare metal in somewhere between 1999-2002.
I tried to cope with Macs until 2004 or 2006. After that Gentoo... Damn it felt good. It was a rough start, but I kinda knew it back then.